Air motor



April 20, 1943.

E. W. WATERMAN AIR MOTOR Filed Aug. 11, 1941 n m k m INVENTOR.

Patented Apr. 20, 1943 UNITED .STATES PATENT OFFICE AIR. MOTOR Earl W. Waterman, Coleville, Calif.

Application August 11, 1941, Serial No. 406,433

2 Claims.

My invention relates to new and useful improvements in air motors.

An important object of my invention i the provision of means for converting an internal combustion engine into an air motor, which means may be easily applied to the engine and requires that but slight changes be made in the engine to effect such conversion.

Still another object of my invention is the provision of means of the above mentioned character that may be easily assembled and applied to the engine and that is efficient and efficacious in the performance of its duties.

Other objects and advantages of my invention will be apparent during the course of the following description.

In the drawing, forming a part of this specification, and wherein like numerals are employed to designate like parts throughout the same.

Figure 1 is a side elevation of a device embodying my invention, parts being shown in elevation and parts in section for clearness of illustration.

Figure 2 is a vertical sectional view taken substantially on the line 2--2 of Figure 1, and

Figure '3 is any enlarged fragmentary vertical sectional view taken on the line 33 of Figure 1.

In the accompanying drawing, wherein for the purpose of illustration, is shown a preferred embodiment of my'invention, the numeral Illdesig nates the block of an internal combustion engine. The block is provided with a pair of laterally spaced cylinder H and I2 the lower ends of which open into the crankcase l3 and the upper ends of which are closedby a cylinder head M in the conventional manner. A crank shaft is mounted for rotation within the crankcase of the engine and the pistons l6 and I! mounted for reciprocation within the cylinders are connected to the crank arms 18 and 19 of the crankshaft by means of the connecting rods 20 and 2 l. One end of the crankshaft extends exteriorly of the crankcase to receive the flywheel 22 and the opposite end thereof extends through the opposite end of the crankcase to receive the spur'gear 23. A cam shaft 24 extends longitudinally through the crankcase above and at one side of the crankshaft and a timing gear 25 carried by one end thereof exteriorly of the casing meshes with the spur'gear 23. The above construction is conventional in all internal combustion engines of this type.

In converting. the engine into an air motor, I remove the intake manifold and close the openings 26 in the engine block by means of-the plates 21 or the like. In addition to removing the in-' the fuel passages which lead from the valve seat to the cylinders. In Figure 2 I have illustrated the portion of the cylinder head overlying the valve seats 28 in which the fuel inlet valves were originally disposed as being devoid of the usual valve accommodating space. The object in reforming the underside of the cylinder head in this manner is to provide a plane surface which will close communication between the intake manifold and the cylinders. Obviously, this result may be accomplished in numerous ways, for instance, a gasket or the like could be inserted between the valve seats and the cylinder head to close the intake manifold; however I have found that the best results are obtained by filling the fuel inlet passages.

Air under pressure is injected into the working chambers 29 in the cylinder head through the valves 30. These valves are identical in their construction and a detailed description of but one will therefore be given. A sleeve 3i has the lower end thereof screw threadedly inserted into the spark plug opening 32 whereby the sleeve will rise vertically from the cylinder head to slidably support the collar 33 of the valve casing34. The

retaining ring 35 encloses the lower portion of thesleeve 3i and the base flanges 36 thereof seat against the upper surface of the cylinder head. Bolt elements 31 extend through the baseflanges of the retaining ring and threadedly engage within sockets 38 formed in the cylinder head to securely hold the ring associated therewith. The upstanding tubular portion ofthe retaining ring strengthens and supports the sleeve and the upper end 39 thereof provides a seat for limiting the downward sliding movement of the collar 33, which collar is normally held in vertically spaced relation with the seat 39 by means of a coil spring 40. The lower end of a tubular portion 4| is internally recessed as at 42 to receive the valve seat 43 and the portion thereof extending beyond the seat is screw threaded to receive the upper end of the collar 33. The valve seat extends transversely across the vbore of the casing and supports the downwardly seating valve 44, the depending stem 45 of which extends through the seat to hold the enlarged head portion thereof in covering relation with the air inlet ports 46 in the seat. The upper end of the sleeve portion is closed by a plug member 41 and a coil spring 48 interposed between the plug and the head portion of the valve 44 normally holds the valve in the closed position. The stem portion 49 of an upwardly seating valve 50 extends through a central bore 51 provided in the valve plug 52 disposed in the upstanding sleeve 3 I The stem portion-5l extendsabove the valve plug and in axial ly maintained in slightly spaced relation by the resilient action of the coil spring 40. The up Wardly seating valve 50 is also provided with a depending shank 53 upon which .the collar 54 is slidablymountedh The collar rests upon diametrically opposed lugs 55 extending into the bore of the sleeve and a coil spring 56 carried by the... shank has the opposite ends thereof seating against the collar and valve 59 respectively to normally hold the valve in the closed position.

An air inlet duct 51 extends through the wall of the tubular portion of the valve ;ca sing-interme-- diate the plug 41 and the valve seat 43. 'lfhedelivery tube of a pressure tank is connected in the duct 57 whereby air under pressure from the tank will have constant communication with the portion of the valve casing extending between the valve seat 43 and the plug member 41.

In order that the movements of the valve mechanisms may be coordinated with the movements of the pistons l6 and I1, I have mounted a standard 58 on the cylinder head adjacent each of the valves and a rocker arm 59 is pivotally attached to'each of the standards. .One I double lift cams 63 formed on the cam shaft 2 The timing gear 25 has a 2 to 1 ratio with the spur gear 23 of the crankshaftwhereby the push rods will be reciprocated once during each rotation of the crankshaft. The push rodsaare yieldably held in pressed engagement with the cam shaft by means of the coil springs 64 sothat the lower ends thereof will follow the peripheral surface of the cams at all times during their retation. V I

The exhaust ports of the engine are'opened and closed in the conventional manner by means of the poppet valves 65, the push rodsBB of which rest upon the cams 61 formed on the cam shaft, which last mentioned cams open the poppet valves 65 when the pistons are beginning their upstroke and close the said valves when the pistons begintheir downstroke. When the poppet valves 65 are open, air under pressure in the portion of the cylinder extending above the piston is permitted to egress through the exhaust manifold.

68 and as soon as the pistons complete their upstroke, the cams 63 operate to raise the push rods Gil to actuate the air inlet valve mechanisms 39.

As best illustrated in Figure 2, upward sliding movement of each of the lift rods willraiser the attached end of its respective rocker arm whereby'to cause the opposite end of the rocker arm to press downwardly on the plug 61 of the inlet valve mechanism with'which it is associated. Downward pressure of the rocker arm willr',

cause the valve casing to slidedownwardly on the sleeve 3 against the resilient action of the coil spring 40. The casing will slide downwardly on the sleeve a suflicient distance to effect engagement of the stem portions of the valves Manda 50 whereby to eifect simultaneous unseating of the valves. As soon as the downwardly seating valve 44 is opened air under pressure will pass the push rods 60 in the elevated position until the piston nears the end of its downstroke, at which time the cam will move to a position to permit the springs 40 and 64 to lower the push rod and close the inlet valve mechanism. When the piston begins its upstroke, the related cam 61 will open the poppet valve 65 to permit the air in the "cylinder to discharge through the exhaust manifold 68. v

It is to be understood that the pistons reciprocate alternately in the convention-almanner so that one of the pistons is making its downstroke while the other ofthe pistons is making its upstroke.' I I The form of my invention herewith shown 'an 'd described is to be taken as a preferred example of the same, and various changes in size, shape and arrangement of parts may be resorted to without departing from the spirit of myjnvention or the scope of the appended claims.

WhatIclaim is: 1 v

1. In an air motor having a cylinder and a piston mounted for reciprocation within the cylinder to provide a working chamber therein", said chamber having an air inlet port, a valve mechanism for admitting air into the working chamber of the motor comprising a source of fluid pressure, a sleeve communicating with the. air inlet port of the'working chamber, a valve seat in the said sleeve, an upwardly seating valve having an upstanding stem portion disposed .Within the sleeve, spring means normally holding the valve against the said seat, a casing-slidably mounted on the sleeve having an air inletcommunicatingwith the source of fluid pressure, va valve seat in the casing below the said airin'letQa downwardly seating valve disposed within the casing, said valve having a depending" stem'portion engageable withthe stern of the first mentioned valve, and spring means normally holding ting air into the working chamber comprising a source of fluid pressure, a sleeve communicating with the air inlet port, a valve seat in said sleeve,

afirst valve having a stern located in said sleeve,

spring means normally holdingsaid first valve against said seat, a casing slidably mounted :on

the sleeve having an air inlet communicating with the source of fluid pressure, a second valve seat in said casmg a second valve insaid casing,

said second valve'havin g a stem engageable with said first mentioned stem, and spring means n on mally holding th e s econd valve against said'last en ion atwh r by. Sh of the casing along the sleeve brings thevalve stems-into engagement one with the other toeffect coactin unseating of the valves associated therewitnjg EARL W. WATERMAN. 

